ESPE Abstracts

Objective: Central precocious puberty (CPP) is defined as early activation of the hypothalamic-pituitary-gonadal axis. The gonadotropin releasing hormone (GnRH) stimulation test has become widely used in the evaluation of CPP. However, intravenous GnRH is often not readily available for commercial use. Therefore, we aimed to evaluate the diagnostic accuracy of the Triptorelin test compared to the GnRH test.

Methods: A total of 656 girls were referred to Ajou University Hospital for evaluation of precocious puberty between 2020 and 2021. A total of 390 patients underwent the GnRH stimulation test using intravenous GnRH (Relefact, 100ug) from May 2020 to Mar 2021, and a total of 266 patients performed the test using Triptorelin (100ug) from April 2021 to December 2021. The inclusion criteria for this cohort were (i) objective breast budding appeared before the age of 8 years and (ii) advanced bone age more than 1 year over the chronological age. During simulation test, serum luteinizing hormone (LH) and follicle stimulation hormone (FSH) levels were acquired at 0, 30, 45, 60, 90, and 120 min after the injection.

Results: Of the 656 subjects, 217 (33.1%) were included in the pubertal response group and 439 (66.9%) were in the prepubertal response group. Triptorelin test mainly showed the peak of LH level at about 60 minutes, and then showed a tendency to decrease gradually. In the examination using Relefact, the peak value of LH appeared mainly at 30 minutes and then showed a tendency to gradually decrease. Based on the ROC curve, the highest diagnostic accuracy for CPP (AUC = 0.998, sensitivity 96.9%, specificity 89.3%) at 120 min was at a LH level above 4.65 IU/L.

Conclusion: In situations where intravenous GnRH stimulation test is limited, subcutaneous triptorelin stimulation test can be considered as an alternative. In addition, a single LH measurement obtained 120 minutes after triptorelin stimulation may be adequate for diagnosing CPP.